There is currently a demand for pneumatic tires to be improved in various performance areas. Such improvement may be realized through the design of tread patterns. Heavy duty tires have been provided with a tread pattern designed with improved traction performance in mind.
For example, a heavy duty pneumatic tire is known which improves both traction characteristics on bad roads until the terminal stage of wear and wet performance at high-speeds in a compatible manner (see Japanese Unexamined Patent Application Publication No. H09-136514A). This heavy duty pneumatic tire is a pneumatic tire that includes a tread provided with at least one circumferential groove extending in the circumferential direction, and a plurality of lateral grooves disposed on opposite sides of the circumferential groove at intervals in the circumferential direction, the plurality of lateral grooves being connected to the circumferential primary groove, wherein
(1) the at least one circumferential groove extends in the circumferential direction in a tread central region corresponding to 50% of the tread width;
(2) a groove depth of the at least one circumferential groove is 5% or greater of the tread width; and
(3) a lateral groove of the plurality of lateral grooves provided in at least both side portions of the tread has a groove depth 109% of the groove depth of the at least one circumferential groove.
This pneumatic tire is described as being capable of improving traction characteristics on bad roads and wet performance at high speeds in a compatible manner.
The heavy duty pneumatic tire described above is capable of improved traction characteristics in the terminal stage of wear. However, up until the terminal stage of wear, the tread center region wears more quickly than the tread shoulder regions.